It’s no secret that public opinion on marijuana has shifted dramatically in recent years. Is this the beginning of the end for the anti-marijuana generation? Some would say so.

Advocacy of marijuana legalization is fast becoming a popular standpoint among Americans. According to Gallup polls, public support for marijuana legalization reached a record-high of 50% in 2011 and remained relatively consistent for the most part of 2012. Last November’s poll showed only a slight dip in support, from 50% to 48%.

You might be wondering just who these supporters are. Well, it shouldn’t come as much of a surprise to hear that Gallup found support for marijuana to be inversely proportional to age, with as much as 62% of 18-to-29 year-olds in favor of legalization, down to just 31% of those 65 and older. Indeed, the pro-marijuana movement appears to be largely driven by young voters.

Before you discredit this group for their youth, consider this. Similar surveys by CNN and Pew show that support for marijuana legalization comes from a wealthier and more highly educated demographic. Interestingly, CNN also found that whites were more likely to support legalization than non-whites, despite the fact that blacks are more likely to be arrested for drug possession.

Such high levels of support for marijuana are in stark contrast with the traditional norm. When Gallup first polled the public about marijuana legalization in 1969, only 12% of Americans were in favor. And as recently as 2005, only about a third of Americans indicated support for legalization.

What happened between 2005 and 2011 is anyone’s guess, although some explanations appear more convincing than others.

A major factor in shifting public opinion could very well be the growing number of states that have legalized medical marijuana. Between 2005 and 2011, legalization measures were passed in seven separate states as well as the District of Columbia. This brought the total number of Americans living in legal medical marijuana states to over 90 million, representing roughly 1 in 4 of the overall population.

By the time Delaware’s marijuana legislation was signed into law in mid-2011, over 1 million Americans had authorization to access medical marijuana.

Disregarding medical marijuana for a moment, national surveys show that illicit marijuana has also increased, albeit to a much smaller degree. From 2005 to 2011, the proportion of high school students that reported using marijuana at some point in their lives crept upward from 38% to 40% – perhaps explaining why support for legalization is highest among the younger demographic. Prevalence of past month marijuana use within the overall population also rose during this time.

Still, this only scratches the surface of what really undermines the anti-marijuana mindset. What many seem to overlook is the scientific momentum that marijuana has gained in recent years.

The increase in statewide legalization measures comes as a direct result of scientific evidence which finds medical marijuana to be an effective treatment for a wide range of conditions. Furthermore, long-standing public fear of marijuana’s damaging effects on the brain and lungs have been debunked time and time again by overwhelming proof of the contrary.

As anti-marijuana campaigns dwindle in their efforts, many Americans are beginning to see the benefits of policy reform.

Legalization of recreational marijuana in Colorado and Washington following November’s election has strongly contributed to public awareness of the discrepancy between public opinion and federal policy. As it stands today, legalization measures in Colorado and Washington seem like only a minor indication of things to come as a nationwide pro-marijuana generation takes form.